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Birt‐Hogg‐Dubé (BHD) syndrome is associated with the development of hereditary renal cell carcinoma (RCC) and is caused by a germline mutation in the folliculin gene. Most cases of BHD syndrome‐associated RCC (BHD‐RCC) are less aggressive than sporadic clear cell RCC and multifocal. Therefore, it is critical to distinguish BHD‐RCC from its sporadic counterparts to identify and monitor affected families and to preserve renal function for as long as possible. The World Health Organization/International Society of Urological Pathology consensus classification defined distinct entities for certain hereditary RCC; however, BHD‐RCC was not included in this classification. Although the clinical features and molecular mechanisms of BHD‐RCC have been investigated intensively over the last two decades, pathologists and urologists occasionally face difficulties in the diagnosis of BHD‐RCC that require genetic testing. Affected patients usually have miscellaneous benign disorders that often precede renal carcinogenesis. In the present review, we summarize the current understanding of the histopathological features of BHD‐RCC based on our epidemiological studies of Japanese families and a literature review. Pathological diagnostic clues and differential diagnosis of BHD‐RCC from other hereditary RCC are also briefly discussed.  相似文献   
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BackgroundClear-cell renal cell carcinoma (ccRCC) is one of the most common malignancies in humans and is usually associated with poor outcomes. Cancers are considered to be genetic diseases. Therefore, a better understanding of genetic alterations that are related to disease progression or poor prognosis can help to more precisely identify high-risk patients and treat them more effectively. The aim of this study was to examine the frequency of whole chromosome 9 loss (monosomy of chromosome 9) and its prognostic value in patients with ccRCC.Materials and MethodsSingle nucleotide polymorphism-based chromosome microarray (CMA) analysis was performed on 103 resected specimens from patients with ccRCC who had undergone partial or radical nephrectomy between January 2002 and March 2017 at Fox Chase Cancer Center. Monosomy 9 was correlated with clinicopathologic parameters and recurrence-free survival.ResultsChromosome 9 loss was detected in 31 (30%) of 103 tumors. Tumors with chromosome 9 loss had higher histologic grade (3 and 4; P < .001) and pathologic stage (P < .001). In 59 patients with non-metastatic ccRCC, chromosome 9 loss was also associated with higher recurrence rate and shorter recurrence-free survival (RFS) (12-month RFS, 77.8%; 95% confidence interval, 36.5%-93.9% for chromosome 9 loss vs. 95.7%; 95% confidence interval, 84.0%-98.9% for no loss; P = .002).ConclusionsChromosome 9 loss was found in 30% of patients with ccRCC and correlated with higher grade, advanced stage, and shorter RFS in patients with Stage I to III ccRCC.  相似文献   
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目的:探讨 miR-9 通过靶向 E 盒结合锌指蛋白 2(zinc finger E-box binding homeobox 2,ZEB2)对小细胞肺癌(small cell lung cancer,SCLC)细胞生物学行为的调控作用,分析miR-9在SCLC中的作用及其工作机制。方法:采用qPCR、WB和免疫组化方法检测于2018年2月至2019年11月于河北医科大学第四医院肿瘤内科接受手术治疗的67例SCLC患者癌组织及癌旁组织中ZEB2的表达。采用TargetScan预测miR-9的潜在靶基因并通过双荧光素酶报告基因试验、qPCR和WB法进行验证。CCK-8法、流式细胞术和Transwell实验检测miR-9和ZEB2 过表达对 NCI-H446 的生物学行为影响,WB法检测对细胞中E-cadherin,N-cadherin和Vimentin蛋白表达的影响。利用miR-9过表达NCI-H446细胞构建SCLC裸鼠移植瘤模型,观察miR-9对裸鼠移植瘤生长的影响。结果:SCLC组织中ZEB2的mRNA和蛋白表达水平明显高于癌旁正常组织(P<0.01)。miR-9在ZEB2的3'' UTR上具有潜在的结合位点,与对照组相比,miR-9过表达组NCI-H446细胞中ZEB2的mRNA和蛋白表达水平明显降低(P<0.01),细胞增殖、迁移和侵袭能力均显著下降(P<0.05或P<0.01),促EMT蛋白表达减少,而同时过表达ZEB2能够逆转上述影响。体内实验中,miR-9过表达组移植瘤体积、重量均明显低于对照组(P<0.05或P<0.01)。miR-9组裸鼠肿瘤组织中和ZEB2蛋白的表达均较对照组明显降低(P<0.01)。结论:miR-9通过靶向调控ZEB2从而抑制SCLC细胞的生物学行为以及NCI-H446裸鼠移植瘤的生长。  相似文献   
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《Molecular therapy》2020,28(6):1432-1441
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Objectives: This study aimed to investigate the expression of SOX2, SOX9, p53, and β-catenin in hepatocellular carcinoma (HCC) and their correlation with clinicopathological parameters of prognostic importance. Materials and Methods: Seventy-five patients were enrolled in this study. All patients had full clinical and follow-up data and available paraffin blocks. Immunohistochemical analysis was performed and correlated with clinicopathological factors and patient survival. Results: We detected the positive expression of SOX2, SOX9, p53, and β-catenin in 76%, 50.7%, 50.7%, and 77.9% of HCC specimens respectively. All studied markers showed a significant increase in the expression in tumor tissue specimens compared to non-tumor tissue. Both SOX2 and SOX9 expressions were significantly associated with adverse prognostic factors in HCC. Significant positive correlations were found between SOX2 and SOX9 and both p53 and β-catenin expression (r= 0.528, 0.485 and; r = 0.253, 0.327, respectively; p < 0.0001 for both of them). Regarding survival, we found that HCC patients with positive SOX2 and SOX9 expressions had significantly shorter overall survival (p=0.0001, each). Additionally, larger tumor size, tumor grade, high stage, tumor multiplicity, presence of cirrhosis, tumor necrosis, high p53 expression, and positive β-catenin expression were independent predictors of worse survival. A multivariate Cox analysis revealed that tumor grade, stage, p53, and SOX2 expression were independent predictors of unfavorable prognosis in overall survival (p=0.0001, p=0.0001,p=0.033; and p=0.003, respectively). Conclusions: Our findings might provide an insight into SOX2 and SOX9’s role in HCC and suggest that SOX2 might be targeted for HCC therapy.  相似文献   
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The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with Ki values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with Km values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CLR) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CLR (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CLR of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates.  相似文献   
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SEPT9是13个Septin同源基因家族之一,参与调控众多过程,包括细胞分裂、细胞极化、细胞迁移以及线粒体分裂等。研究表明在众多肿瘤中,SEPT9都发挥着作用,尤其在结直肠肿瘤研究领域,外周血SEPT9基因甲基化检测更是研究热点,其检测的敏感度和特异度相对于其他糖蛋白肿瘤标志物、粪便隐血试验和粪便免疫化学测试等更具有优势,相对于结直肠镜等侵入性检查更节约成本,同时有着更好的依从性。本文对SEPT9的功能、与结直肠癌之间的关系以及对结直肠肿瘤的筛查及诊断价值做一综述。  相似文献   
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